I'd like to believe Asami goes case by case. Like it doesn't matter if they're male or female. Ehehehe
Asami is canonically bisexual.
asami trying to help fei long. but then fei long fell in love with asami.
from yamanae ayano website :
" Attendee: Was Feilong in love with Asami?
Yamane-sensei: Feilong had romantic feelings for Asami, and that’s why he clung to Asami so strongly. But Asami was seeking something different from Feilong. If I had to say, he wanted friendship or a sense of camaraderie, maybe. "
I wonder if Asami is gay or straight before he met Aki. But he did meddle with Fei Long a bit and he's not afraid to show affection towards Aki in public or around his subordinate. Guess he's gay from the beginning.